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1.
Public Health ; 225: 311-319, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37972494

RESUMO

OBJECTIVES: In 2020, Brazil experienced two concurrent public health challenges related to respiratory disease: wildfires and increased mortality due to the coronavirus (COVID-19) pandemic. Smoke from these wildfires contributed to a variety of air pollutants, including fine particulate matter (PM2.5). The present study aims to investigate the effects of environmental and socio-economic factors on COVID-19 hospitalisation in the Pantanal. STUDY DESIGN: Ecological retrospective study. METHODS: We applied a multilevel negative binomial model to relate monthly hospitalisation data with environmental variables. RESULTS: We showed that monthly PM2.5 concentration levels had the greatest influence on the increase in hospitalisations by COVID-19 in the elderly (23 % increase). The Gini index, a coefficient that reflects income inequalities, also had a positive association with COVID-19 hospitalisations (18 % increase). Higher temperatures and humidity were protective factors, showing a 15 % and 14 % decrease in hospitalisations, respectively. The results of the present study suggest that high PM2.5 exposure contributed to the increase in COVID-19 hospitalisations, as did the social inequalities of each municipality. CONCLUSIONS: The present study highlights the importance of gathering evidence supported by multiple information sources to guide decision-making and identify populations needing better public health systems.


Assuntos
COVID-19 , Incêndios Florestais , Humanos , Idoso , Fumaça/efeitos adversos , Áreas Alagadas , Estudos Retrospectivos , Brasil/epidemiologia , COVID-19/epidemiologia , Material Particulado/análise
2.
Braz J Biol ; 82: e261227, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35976355

RESUMO

The nutrient stress hypothesis predicts that galling insects prevail on host plants growing in habitats with soils of low nutritional quality. Caryocar brasiliense (Caryocaraceae) is host to four different leaf-galling insects. These insects have the potential to cause a reduction in the production of C. brasiliense fruits, an important source of income for many communities in Brazil. We studied the effects of soil physical and chemical characteristics on the abundance, species richness, and diversity of galling insects and their natural enemies on C. brasiliense trees growing under three different soil conditions. Our data corroborate the hypothesis that in nutritionally poor (e.g., lower phosphorus content) and worse physical textures (e.g., sandy) soils, host plants support higher species richness and diversity of galling insects. However, the abundance of Eurytoma sp. (the most common gall in C. brasiliense), was correlated with a higher phosphorus concentration in the soil (better nutritional condition). The percentage of galled leaflets and the area of leaflets occupied by Eurytoma sp galls were higher in the more fertile soil. In this soil, there was greater abundance, species richness, and diversity of parasitoids of Eurytoma sp. (e.g., Sycophila sp.) and predators (e.g., Zelus armillatus). Our data indicate the importance of habitat quality in the composition of the galling insect community and the impact of soil properties in mediating the distribution of these insects in C. brasiliense.


Assuntos
Malpighiales , Árvores , Animais , Biodiversidade , Insetos , Fósforo , Plantas , Solo
3.
Braz J Biol ; 84: e257975, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35588516

RESUMO

Galling insects are abundant in nature, found in many ecosystems globally, with species attacking plants of economic importance. We studied the effects of free-feeding organisms on the abundance of galling insects on Caryocar brasiliense (Caryocaraceae) trees in the Brazilian Cerrado (Savanna). Percentage of defoliation and the number of phytophagous mites or number of phytophagous Hemiptera correlated negatively with percentage of galled leaves and the parasitoid Eurytoma sp. (Hymenoptera: Eurytomidae) adults, respectively. Percentage of galled leaves and the numbers of Eurytoma sp. adults and phytophagous mites correlated positively with spiders. Numbers of mites and Hemiptera phytophagous correlated positively with those of lady beetles and Sycophila sp. (Hymenoptera: Eurytomidae), respectively. The number of Ablerus magistretti Blanchard (Hymenoptera: Aphelinidae) adults correlated negatively with Sycophila sp. The number of Agistemus sp. (Acari: Stigmaeidae) correlated, negatively and positively, with those of lady beetles and phytophagous mites, respectively. Free-feeding herbivores affected the presence of galling insects (Hymenoptera) on C. brasiliense trees, competing for food and space. The same was observed between two parasitoids of Eurytoma sp. galling insect, which can reduce the natural biological control of this pest.


Assuntos
Besouros , Hemípteros , Himenópteros , Malpighiales , Ácaros , Animais , Brasil , Ecossistema , Pradaria , Humanos , Insetos , Plantas , Árvores
4.
Braz. j. biol ; 77(4): 762-773, Nov. 2017. tab
Artigo em Inglês | LILACS | ID: biblio-888812

RESUMO

Abstract Considering that the economic valuation of ecosystem services is a useful approach to support the conservation of natural areas, we aimed to estimate the monetary value of the benefits provided by a protected area in southeast Brazil, the Serra do Cipó National Park. We calculated the visitor's willingness to pay to conserve the ecosystems of the protected area using the contingent valuation method. Located in a region under intense anthropogenic pressure, the Serra do Cipó National Park is mostly composed of rupestrian grassland ecosystems, in addition to other Cerrado physiognomies. We conducted a survey consisting of 514 interviews with visitors of the region and found that the mean willingness to pay was R$ 7.16 year-1, which corresponds to a total of approximately R$ 716,000.00 year-1. We detected that per capita income, the household size, the level of interest in environmental issues and the place of origin influenced the likelihood that individuals are willing to contribute to the conservation of the park, as well as the value of the stated willingness to pay. This study conveys the importance of conserving rupestrian grassland and other Cerrado physiognomies to decision makers and society.


Resumo Dado que a valoração econômica de serviços ecossistêmicos é uma abordagem útil para incentivar a conservação de áreas naturais, tivemos como objetivo estimar o valor monetário dos benefícios fornecidos por uma área protegida no sudeste do Brasil, o Parque Nacional da Serra do Cipó. Calculamos a disposição a pagar dos visitantes pela conservação dos ecossistemas abrangidos pela área protegida, usando o método da valoração contingente. Localizado em uma região que sofre intensa pressão antrópica, o Parque Nacional da Serra do Cipó é composto majoritariamente por campos rupestres, além de outras fitofisionomias do Cerrado. Realizamos 514 entrevistas com os visitantes da região e encontramos uma disposição a pagar média de R$ 7,16 ano-1, o que corresponde ao total de aproximadamente R$ 716.000,00 ano-1. Detectamos que renda per capita, número de dependentes, nível de interesse por temas relacionados ao meio ambiente e local de origem influenciam a probabilidade de o indivíduo estar disposto a contribuir para a conservação do parque, assim como o valor da disposição a pagar declarada. Este estudo atrai atenção dos tomadores de decisão e da sociedade para a importância de se conservar os campos rupestres e outras fitofisionomias do Cerrado.


Assuntos
Ecossistema , Conservação dos Recursos Naturais/economia , Parques Recreativos/economia , Brasil
6.
Plant Biol (Stuttg) ; 19(5): 806-817, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28627760

RESUMO

Flowering and fruiting are key events in the life history of plants, and both are critical to their reproductive success. Besides the role of evolutionary history, plant reproductive phenology is regulated by abiotic factors and shaped by biotic interactions with pollinators and seed dispersers. In Melastomataceae, a dominant Neotropical family, the reproductive systems vary from allogamous with biotic pollination to apomictic, and seed dispersal varies from dry (self-dispersed) to fleshy (animal-dispersed) fruits. Such variety in reproductive strategies is likely to affect flowering and fruiting phenologies. In this study, we described the reproductive phenology of 81 Melastomataceae species occurring in two biodiversity hotspots: the Atlantic rain forest and the campo rupestre. We aim to disentangle the role of abiotic and biotic factors defining flowering and fruiting times of Melastomataceae species, considering the contrasting breeding and seed dispersal systems, and their evolutionary history. In both vegetation types, pollinator-dependent species had higher flowering seasonality than pollinator-independent ones. Flowering patterns presented phylogenetic signal regardless of vegetation type. Fruiting of fleshy-fruited species was seasonal in campo rupestre but not in Atlantic rain forest; the fruiting of dry-fruited species was also not seasonal in both vegetation types. Fruiting showed a low phylogenetic signal, probably because the influence of environment and dispersal agents on fruiting time is stronger than the phylogenetic affinity. Considering these ecophylogenetic patterns, our results indicate that flowering may be shaped by the different reproductive strategies of Melastomataceae lineages, while fruiting patterns may be governed mainly by the seed dispersal strategy and flowering time, with less phylogenetic influence.


Assuntos
Melastomataceae/fisiologia , Reprodução/fisiologia , Animais , Flores/fisiologia , Frutas/fisiologia , Filogenia , Polinização/fisiologia
7.
Braz J Biol ; 77(4): 762-773, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28562788

RESUMO

Considering that the economic valuation of ecosystem services is a useful approach to support the conservation of natural areas, we aimed to estimate the monetary value of the benefits provided by a protected area in southeast Brazil, the Serra do Cipó National Park. We calculated the visitor's willingness to pay to conserve the ecosystems of the protected area using the contingent valuation method. Located in a region under intense anthropogenic pressure, the Serra do Cipó National Park is mostly composed of rupestrian grassland ecosystems, in addition to other Cerrado physiognomies. We conducted a survey consisting of 514 interviews with visitors of the region and found that the mean willingness to pay was R$ 7.16 year-1, which corresponds to a total of approximately R$ 716,000.00 year-1. We detected that per capita income, the household size, the level of interest in environmental issues and the place of origin influenced the likelihood that individuals are willing to contribute to the conservation of the park, as well as the value of the stated willingness to pay. This study conveys the importance of conserving rupestrian grassland and other Cerrado physiognomies to decision makers and society.


Assuntos
Conservação dos Recursos Naturais/economia , Ecossistema , Parques Recreativos/economia , Brasil
8.
Braz. j. med. biol. res ; 49(3): e5003, Mar. 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-771936

RESUMO

Fractionation of the EtOH extract from aerial parts of Baccharis uncinella C. DC. (Asteraceae) led to isolation of caffeic and ferulic acids, which were identified from spectroscopic and spectrometric evidence. These compounds exhibit antioxidant and anti-inflammatory properties and have been shown to be effective in the prevention/treatment of metabolic syndrome. This study investigated whether the combined treatment of caffeic and ferulic acids exhibits a more significant beneficial effect in a mouse model with metabolic syndrome. The combination treatment with caffeic and ferulic acids was tested for 60 days in C57 mice kept on a high-fat (40%) diet. The data obtained indicated that treatment with caffeic and ferulic acids prevented gain in body weight induced by the high-fat diet and improved hyperglycemia, hypercholesterolemia and hypertriglyceridemia. The expression of a number of metabolically relevant genes was affected in the liver of these animals, showing that caffeic and ferulic acid treatment results in increased cholesterol uptake and reduced hepatic triglyceride synthesis in the liver, which is a likely explanation for the prevention of hepatic steatosis. In conclusion, the combined treatment of caffeic and ferulic acids displayed major positive effects towards prevention of multiple aspects of the metabolic syndrome and liver steatosis in an obese mouse model.


Assuntos
Animais , Masculino , Baccharis/química , Ácidos Cafeicos/administração & dosagem , Ácidos Cumáricos/administração & dosagem , Síndrome Metabólica/prevenção & controle , Substâncias Protetoras/administração & dosagem , Ácidos Cafeicos/química , Colesterol/metabolismo , Ácidos Cumáricos/química , Dieta Hiperlipídica/efeitos adversos , Quimioterapia Combinada/métodos , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Síndrome Metabólica/tratamento farmacológico , Camundongos Endogâmicos C57BL , Modelos Animais , Substâncias Protetoras/química , Triglicerídeos/metabolismo
9.
Braz J Med Biol Res ; 49(3)2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26840707

RESUMO

Fractionation of the EtOH extract from aerial parts of Baccharis uncinella C. DC. (Asteraceae) led to isolation of caffeic and ferulic acids, which were identified from spectroscopic and spectrometric evidence. These compounds exhibit antioxidant and anti-inflammatory properties and have been shown to be effective in the prevention/treatment of metabolic syndrome. This study investigated whether the combined treatment of caffeic and ferulic acids exhibits a more significant beneficial effect in a mouse model with metabolic syndrome. The combination treatment with caffeic and ferulic acids was tested for 60 days in C57 mice kept on a high-fat (40%) diet. The data obtained indicated that treatment with caffeic and ferulic acids prevented gain in body weight induced by the high-fat diet and improved hyperglycemia, hypercholesterolemia and hypertriglyceridemia. The expression of a number of metabolically relevant genes was affected in the liver of these animals, showing that caffeic and ferulic acid treatment results in increased cholesterol uptake and reduced hepatic triglyceride synthesis in the liver, which is a likely explanation for the prevention of hepatic steatosis. In conclusion, the combined treatment of caffeic and ferulic acids displayed major positive effects towards prevention of multiple aspects of the metabolic syndrome and liver steatosis in an obese mouse model.


Assuntos
Baccharis/química , Ácidos Cafeicos/administração & dosagem , Ácidos Cumáricos/administração & dosagem , Síndrome Metabólica/prevenção & controle , Substâncias Protetoras/administração & dosagem , Animais , Ácidos Cafeicos/química , Colesterol/metabolismo , Ácidos Cumáricos/química , Dieta Hiperlipídica/efeitos adversos , Quimioterapia Combinada/métodos , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Masculino , Síndrome Metabólica/tratamento farmacológico , Camundongos Endogâmicos C57BL , Modelos Animais , Substâncias Protetoras/química , Triglicerídeos/metabolismo
10.
Neotrop Entomol ; 45(1): 44-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26501884

RESUMO

Fluctuating asymmetry (FA) is a parameter to measure developmental stability in plants, which can be altered by disturbances, pollution, and biotic factors such as herbivory. We evaluated the effects of environmental stress and herbivory on the FA levels in individuals of Tibouchina heteromalla (Melastomataceae) that occur in natural and undergoing restoration areas in rupestrian grasslands at Serra do Cipó, Brasil. Individuals were collected and measured in seven restored and five natural areas, totalizing 240 individuals. We found that individuals in restored areas had greater leaf area, higher levels of insect herbivory and FA compared to individuals that occurred in natural areas. In both environments, the proportion of individuals with leaf damage caused by herbivory was higher than the proportion of undamaged individuals. In addition, FA was positively correlated with herbivory and total leaf area in both restored and natural areas. These results suggest that more favorable conditions in the restored areas enhanced leaf growth, resulting in higher FA.


Assuntos
Herbivoria , Insetos , Folhas de Planta/anatomia & histologia , Animais , Brasil , Plantas/anatomia & histologia
11.
J Insect Physiol ; 84: 103-113, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26620152

RESUMO

Biologists who study insect-induced plant galls are faced with the overwhelming diversity of plant forms and insect species. A challenge is to find common themes amidst this diversity. We discuss common themes that have emerged from our cytological and histochemical studies of diverse neotropical insect-induced galls. Gall initiation begins with recognition of reactive plant tissues by gall inducers, with subsequent feeding and/or oviposition triggering a cascade of events. Besides, to induce the gall structure insects have to synchronize their life cycle with plant host phenology. We predict that reactive oxygen species (ROS) play a role in gall induction, development and histochemical gradient formation. Controlled levels of ROS mediate the accumulation of (poly)phenols, and phytohormones (such as auxin) at gall sites, which contributes to the new cell developmental pathways and biochemical alterations that lead to gall formation. The classical idea of an insect-induced gall is a chamber lined with a nutritive tissue that is occupied by an insect that directly harvests nutrients from nutritive cells via its mouthparts, which function mechanically and/or as a delivery system for salivary secretions. By studying diverse gall-inducing insects we have discovered that insects with needle-like sucking mouthparts may also induce a nutritive tissue, whose nutrients are indirectly harvested as the gall-inducing insects feeds on adjacent vascular tissues. Activity of carbohydrate-related enzymes across diverse galls corroborates this hypothesis. Our research points to the importance of cytological and histochemical studies for elucidating mechanisms of induced susceptibility and induced resistance.


Assuntos
Insetos/fisiologia , Células Vegetais/parasitologia , Tumores de Planta/parasitologia , Plantas/parasitologia , Adaptação Fisiológica , Animais , Interações Hospedeiro-Parasita , Reguladores de Crescimento de Plantas/fisiologia
12.
Braz. arch. biol. technol ; 59: e16160287, 2016. tab, graf
Artigo em Inglês | LILACS | ID: biblio-951361

RESUMO

ABSTRACT Although endophytic bacteria impact the health, and ultimately the fitness, of their hosts, our understanding of the diversity of endophytic species remains limited. Here we report on the endophytic microbiota inhabiting the roots, healthy leaves and leaves attacked by a gall-inducing insect of Baccharis dracunculifolia, a species of major economic relevance in South America, using 16S rRNA gene new generation sequencing. Rhodoplanes and Nitrospira were well represented in the communities of roots and leaves; known to be important for nitrogen cycling. The difference in bacterial diversity between healthy and galled leaves was not pronounced. The leaves seem to harbor specialized bacteria with high tolerances to abiotic stresses such as wide variation in temperature, low humidity, shallow and nutrient-poor soils and high solar irradiation. These findings suggest taxon-specific ecological niches in the leaves and roots, which may be the result of different physicochemical characteristics between these structures. This study provides a basis for further investigations and adds significant new information to the current knowledge of the endophytic bacterial composition in B. dracunculifolia.

13.
Plant Biol (Stuttg) ; 17(2): 512-21, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25124804

RESUMO

Understanding factors that modulate plant development is still a challenging task in plant biology. Although research has highlighted the role of abiotic and biotic factors in determining final plant structure, we know little of how these factors combine to produce specific developmental patterns. Here, we studied patterns of cell and tissue organisation in galled and non-galled organs of Baccharis reticularia, a Neotropical shrub that hosts over ten species of galling insects. We employed qualitative and quantitative approaches to understand patterns of growth and differentiation in its four most abundant gall morphotypes. We compared two leaf galls induced by sap-sucking Hemiptera and stem galls induced by a Lepidopteran and a Dipteran, Cecidomyiidae. The hypotheses tested were: (i) the more complex the galls, the more distinct they are from their non-galled host; (ii) galls induced on less plastic host organs, e.g. stems, develop under more morphogenetic constraints and, therefore, should be more similar among themselves than galls induced on more plastic organs. We also evaluated the plant sex preference of gall-inducing insects for oviposition. Simple galls were qualitative and quantitatively more similar to non-galled organs than complex galls, thereby supporting the first hypothesis. Unexpectedly, stem galls had more similarities between them than to their host organ, hence only partially supporting the second hypothesis. Similarity among stem galls may be caused by the restrictive pattern of host stems. The opposite trend was observed for host leaves, which generate either similar or distinct gall morphotypes due to their higher phenotypic plasticity. The Relative Distance of Plasticity Index for non-galled stems and stem galls ranged from 0.02 to 0.42. Our results strongly suggest that both tissue plasticity and gall inducer identity interact to determine plant developmental patterns, and therefore, final gall structure.


Assuntos
Baccharis/fisiologia , Caules de Planta/anatomia & histologia , Animais , Baccharis/anatomia & histologia , Brasil , Dípteros , Interações Hospedeiro-Parasita , Lepidópteros , Folhas de Planta/anatomia & histologia , Folhas de Planta/fisiologia , Caules de Planta/fisiologia
14.
Braz. j. biol ; 73(4): 709-716, 1jan. 2013. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468136

RESUMO

The rupestrian grassland ecosystems provide various goods and services to society and support a significant amount of biological diversity. Notably the rich plant diversity has high levels of endemism and a variety of uses among the local communities and general society. Despite the socio-ecological importance of these ecosystems, they are subjected to significant anthropogenic pressures. The goal of this study is to perform economic valuation of the plant diversity storage service provided by rupestrian grassland ecosystems to provide grounds for the development of conservation policies and encourage sustainable practices in these ecosystems. Given the intense human disturbances and unique flora, the Serra do Cipó (southern portion of the Espinhaço Range in southeast Brazil) was selected for the study. We estimate the monetary value related to the plant diversity storage service provided by the study area using the maintenance costs of native plants in the living collections of the botanical garden managed by the Zoobotanical Foundation - Belo Horizonte (located 97 km from Serra do Cipó). The plant diversity storage value provided by Serra do Cipó ecosystems is significant, reaching US$25.26 million year1. This study contributes to the development of perspectives related to the conservation of rupestrian grassland ecosystems as well as others threatened tropical ecosystems with high biodiversity.


Os ecossistemas de campos rupestres fornecem diversos bens e serviços à sociedade, além de abrigar uma significativa diversidade biológica. Particularmente, a rica biodiversidade vegetal apresenta altas taxas de endemismo e uma grande variedade de usos entre a comunidade local e a sociedade como um todo. Apesar da importância sócio-ecológica desses ecossistemas, eles estão submetidos a significativa pressão antrópica. O objetivo desse estudo é realizar a valoração econômica do serviço de estocagem da diversidade de plantas fornecido pelos ecossistemas de campos rupestres para fornecer subsídios para o desenvolvimento de políticas conservacionistas e estimular práticas sustentáveis nesses ecossistemas. Diante dos intensos distúrbios antrópicos e sua flora única, a Serra do Cipó (porção sul da Cadeia do Espinhaço, Sudeste do Brasil) foi selecionada para este estudo. Estimamos o valor monetário relacionado ao serviço de estocagem da diversidade de plantas fornecido pela área de estudo, utilizando os custos de manutenção de plantas nativas em coleções vivas do jardim botânico da Fundação Zoo-Botânica de Belo Horizonte (localizado a 97 km da Serra do Cipó). O valor do estoque da diversidade de plantas fornecido pelos ecossistemas da Serra do Cipó é significativo, atingindo US$25,26 milhões ano1. Esse estudo contribui para o desenvolvimento de perspectivas relacionadas à conservação dos ecossistemas de campos rupestres assim como outros ecossistemas ameaçados e com alta biodiversidade nos trópicos.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Desenvolvimento Sustentável , Plantas , Brasil
15.
Braz J Biol ; 73(4): 709-16, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24789385

RESUMO

The rupestrian grassland ecosystems provide various goods and services to society and support a significant amount of biological diversity. Notably the rich plant diversity has high levels of endemism and a variety of uses among the local communities and general society. Despite the socio-ecological importance of these ecosystems, they are subjected to significant anthropogenic pressures. The goal of this study is to perform economic valuation of the plant diversity storage service provided by rupestrian grassland ecosystems to provide grounds for the development of conservation policies and encourage sustainable practices in these ecosystems. Given the intense human disturbances and unique flora, the Serra do Cipó (southern portion of the Espinhaço Range in southeast Brazil) was selected for the study. We estimate the monetary value related to the plant diversity storage service provided by the study area using the maintenance costs of native plants in the living collections of the botanical garden managed by the Zoobotanical Foundation - Belo Horizonte (located 97 km from Serra do Cipó). The plant diversity storage value provided by Serra do Cipó ecosystems is significant, reaching US$25.26 million year-1. This study contributes to the development of perspectives related to the conservation of rupestrian grassland ecosystems as well as others threatened tropical ecosystems with high biodiversity.


Assuntos
Conservação dos Recursos Naturais/economia , Ecossistema , Poaceae/classificação , Biodiversidade , Brasil , Gastos de Capital , Conservação dos Recursos Naturais/métodos , Espécies em Perigo de Extinção , Humanos
16.
Braz J Biol ; 72(3): 453-7, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22990814

RESUMO

Our goal was to identify herbivory patterns from two insect guilds associated with Cnidoscolus quercifolius in a tropical deciduous forest in northeastern Brazil. We sampled four different habitats: (1) forest edge, (2) mesic (near to the perennial water source), (3) forest interior and (4) rupestrian fields. Habitat edge had lower leaf damage than rupestrian, mesic and forest interior habitats. Nevertheless, abundance of galls at the edge habitat was higher than at mesic, forest interior and/or rupestrian habitats. There was no difference in gall mortality by natural enemies among the four habitats sampled, demonstrating the absence of any influence of top-down controls related to abundance of galls. Trophic relationships were not related to the patterns of distribution among habitats of two insect herbivorous guilds associated with C. quercifolius. Our results demonstrated that environmental heterogeneity of dry forests can significantly alter important ecological interactions and experimental studies are needed to better understand the mechanisms responsible for differences in herbivory among habitats.


Assuntos
Ecossistema , Euphorbiaceae/parasitologia , Herbivoria/fisiologia , Interações Hospedeiro-Parasita/fisiologia , Insetos/fisiologia , Animais , Brasil , Herbivoria/classificação , Insetos/classificação
17.
Genet Mol Res ; 11(4): 3729-34, 2012 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-22930434

RESUMO

Transfer of molecular markers is widely used in conservation genetic studies. We investigated the transferability of simple sequence repeat (SSR) markers developed for Enterolobium cyclocarpum to E. contortisiliquum, a tropical tree widely distributed in dry forests. A set of 9 evaluated SSR markers were amplified in E. contortisiliquum and the degree of polymorphism was assessed in 8 trees sampled from each of 5 populations from central Brazil. All loci were polymorphic and the mean number of alleles for all loci was 6. In addition, all pairs of SSR markers were in linkage equilibrium. For most loci, the observed heterozygosity was higher than the expected heterozygosity under Hardy-Weinberg equilibrium, with fixation indices not significantly different from zero. The combined probability of paternity exclusion was high and the probability of identity was very low. We conclude that these SSR markers developed for E. cyclocarpum are applicable for genetic studies of E. contortisiliquum.


Assuntos
Fabaceae/genética , Repetições de Microssatélites/genética , Árvores/genética , Clima Tropical , Alelos , Sequência de Bases , Brasil , Loci Gênicos/genética , Marcadores Genéticos , Variação Genética , Geografia , Dados de Sequência Molecular , Motivos de Nucleotídeos/genética
18.
Neotrop Entomol ; 41(6): 518-20, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23949678

RESUMO

Several plant parts or organs are often used by insects for aggregation and even as resting areas. We first report the use of fruits of the legume Mimosa foliolosa pachycarpa as a night shelter for Megachile (Pseudocentron) botucana Schrottky (Hymenoptera: Megachilidae) in Serra do Cipó, southeastern Brazil. Only a single bee was found per fruit, in 86 fruits out of 1,003 fruits opened. The present findings augmented the occurrence of the phenomenon among bees, which is new to the harsh mountaintop environments in the Brazilian rupestrian fields.


Assuntos
Fabaceae , Frutas , Himenópteros/fisiologia , Comportamento de Nidação , Animais , Feminino , Masculino
19.
Braz J Biol ; 71(1): 47-56, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21437398

RESUMO

We report on the richness of galling insects in the altitudinal wetland forests of Pernambuco State, Northeastern Brazil. We found 80 distinct types of insect galls on 49 species of host plants belonging to 28 families and 35 genera. Most of the galled plant species belong to Nyctaginaceae, Fabaceae, Meliaceae, Sapindaceae and Myrtaceae. The most common gall were spheroid and globoid; most galls were glabrous, predominantly green and with one chamber, and on the leaves. Most galls were induced by Cecidomyiidae (Diptera). The results of this study contribute to existing knowledge richness of galling insects and host-plant diversity in the altitudinal wetland forests of Northeastern Brazil.


Assuntos
Biodiversidade , Insetos/classificação , Tumores de Planta/parasitologia , Altitude , Animais , Brasil , Interações Hospedeiro-Parasita , Insetos/fisiologia , Tumores de Planta/classificação , Árvores , Áreas Alagadas
20.
Braz J Biol ; 70(3 Suppl): 723-8, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21085778

RESUMO

Leaf galls induced by a still undescribed new species of Cecidomyiidae (Diptera) are frequent on leaves of Clusia arrudae Planchon & Tirana (Clusiaceae) in the rupestrian fields at 1400 m a.s.l. in Serra do Cipó, Minas Gerais, Brazil. Galls were 7.1 ± 0.7 mm in diameter, one chambered with only one larva inside. Gall tissue is green and soft. Assessments of photosynthetic capacity using chlorophyll-a fluorescence measurements revealed that photosynthetic performance of gall tissue and healthy leaf tissue were rather similar. Hence, the morphological changes due to gall development were not associated with significant changes in the photosynthetic capacity of the tissue.


Assuntos
Clusia/fisiologia , Dípteros , Fotossíntese/fisiologia , Tumores de Planta/parasitologia , Animais , Clusia/parasitologia
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